Preheat oven to 400°F or 200C. Line large baking sheet with parchment paper.

In large bowl, vigorously whisk together flour, sugar, baking soda, baking powder, and salt. Stir in the candied ginger, lemon zest and fresh ginger until evenly mixed.

Create a well in the center of flour and pour in melted butter and buttermilk (or buttermilk substitute). Gently mix with a wooden spoon until flour mixture is just moistened. Don't over-mix. Mixture should look very shaggy.

Divide mixture into two balls and flatten each onto a floured surface into 1-inch thick, 6-inch wide circle. Slice each round into 6 wedges. Transfer to parchment paper-lined baking sheet, spacing at least inch apart. Sprinkle with coarse sugar.

Bake for 18-20 minutes. Cool for 5 minutes before eating.